Performance issues with 2x 6870 crossfire. Help!

I just bought a second Sapphire HD 6870 to compliment the one I bought just a couple months ago. GPU-z has been recognizing both cards, so I was expecting to see a performance increase in my games. WRONG!

I have noticed that my games have been performing much better when I disable crossfire. In every game I try (I have tried about 10-15 different games from my steam library), my FPS is about 10-20 less with crossfire, as will as being a lot more stuttery.

I have done a clean sweep with DriverSweeper in safe mode, downloaded the latest CAP for 11.12, and disabled all of my OC'ing. What am I missing?

Specs:
CPU: AMD FX4100 @ Stock(OC'd to 4.4GHz before I started troubleshooting this problem!)
Mobo: MSI 990XA-GD55
PSU: SILVERSTONE Strider Essential series ST60F-ES 600W (42A on the 12v rail)
OS: W7 64bit
RAM: 16gb Corsair Vengeance
12 answers Last reply
More about performance issues 6870 crossfire help
  1. Bottlenecking :S Spend 30 bucks and get a hyper 212 evo and overclock!!!!!!!!!!!!!!
  2. amuffin said:
    Bottlenecking :S Spend 30 bucks and get a hyper 212 evo and overclock!!!!!!!!!!!!!!


    I am aware that buying one of the new bulldozers was a very bad idea, but that doesn't help explain the decrease in performance at all. I would understand my FPS staying the SAME if bottlenecking was the only problem here, but it isn't. It's literally lowering the performance.
  3. Because your cpu can't keep up with 2 6870, but it can keep up with 1.
  4. amuffin said:
    Because your cpu can't keep up with 2 6870, but it can keep up with 1.


    Hmm. Overclocking doesn't seem to change much. I had it going steady at 4.4GHz before I disabled it. Could it be my PSU?
  5. You sir might need to join us intel fanboys. Say what you will, but deep down you know the 2500k is calling your name.
  6. leblanc93 said:
    Hmm. Overclocking doesn't seem to change much. I had it going steady at 4.4GHz before I disabled it. Could it be my PSU?

    Did you download & installed the Catalyst Application Profile (cap)?
    http://downloads.guru3d.com/AMD-Catalyst-Application-Profile---11.8-CAP5-download-2782.html
    http://sites.amd.com/us/game/downloads/pages/crossfirex-app-profiles.aspx
  7. hiimnickwhoareu said:
    You sir might need to join us intel fanboys. Say what you will, but deep down you know the 2500k is calling your name.


    I can honestly say that I wish I had the means to make an intel build. I am a starving college student. That's why the FX series looked so appealing. The one time I don't look up benchmarks, right? :pfff:

    If I could do it all over, I would be rocking a 2500k, BUT! There's no way I can afford a new mobo AND a 2500k at this point in my life.

    Any more ideas anyone? I still think my PSU may be part of the problem. After re overclocking I'm getting crashes, start-up issues, and BSODS.

    Power supply??? Anyone??? ANYONE?! :cry:
  8. Did you test the second/new card by itself to make sure its working correctly?
  9. get the 12.1 preview drivers, worked for me.
  10. 4745454b said:
    Did you test the second/new card by itself to make sure its working correctly?

    I did try that, thanks. It's working just fine. Also, both of my pci-e slots are x16, so no problems there.
  11. guavasauce said:
    get the 12.1 preview drivers, worked for me.

    How similar was your problem in comparison to mine? Same cards? Same cpu? A little more info would really help me out.
  12. yes i have the same problem here 2 6870CF bad Performance and have a fx 8120 and i have a AMD Phenom II X4 OC at 4.1GHz and still get bad Performance its low gpu usage ever one who have 6870CF seem to have the same problem i think its the driver catalyst but some games like BF3 you will get much better Performance.
Ask a new question

Read More

Radeon Performance Crossfire Graphics